Nitrogen Rejection

CB&I has extensive experience and capabilities in nitrogen rejection from natural gas streams with both cryogenic processes for larger gas volumes and membrane systems for smaller gas volumes.

Cryogenic. CB&I has provided the conceptual design and basic engineering for feed rates 50 to 450 MMSCFD. The basic engineering also included amine treating,molecular sieve dehydration, helium extraction & recovery, NGL recovery, plus inlet and residue gas compression. For four of those projects, we provided full EPC services, and EPF services for one project. Both in house and third party technologies were used. The 450 MMSCFD plant is the largest single train NRU in North America.

Membranes.CB&I and Membrane Technology and Research have an alliance for the technical and commercial development of membrane systems for gas processing and treating applications. Applications include gas dehydration, hydrocarbon dew point control, NGL separation, carbon dioxide, nitrogen, and hydrogen sulfide removal, and fuel gas conditioning. The membrane used for CO2 removal offers exceptional performance in the essential design areas of flux and selectivity.

MTR is the only manufacturer of a membrane for nitrogen removal. The membranes used for nitrogen removal require very little pretreatment. These membranes have been used for federates up to 20 MMSCFD and nitrogen composition up to 15%. CB&I would provide the modules for any pretreatment and the membrane systems.